Not so much As You Like It; rather, 'As the Director Pleases'. David Lan's star-encrusted production of Shakespeare's fond and melancholy play does away with the Forest of Arden and sets the action in 1940s France. It opens to the swing of an accordion emerging from the shadows; it has Phoebe in a beret, the shepherd in a blue smock, and a bevy of girls in clumpy heels and calf-length coats. Nearly everyone shouts.

You can make a list of reasons for this translocation. Shakespeare's romance is scattered with French names; the pastoral on which he based his play was set in the woods of the Ardennes (Arden was a bit of a joke); even the most dulcet of the drama's many songs are veined with melancholy and have that in common with the husky, post-coital sadness of French chanson.

Still, you'd hardly say any of this amounts to a justification. More fundamental is the movement in As You Like It, as in Forties France, from repression to liberty. But you don't get that healing and freeing here. When Rosalind and Celia run away from court and city, where they've been having a lovely chic time in a Parisian cafe, they land up, thanks to Richard Hudson's design, in a nasty, black rehearsal room and, later, surrounded by spiky tufts of grass and flatly painted trees. They can't flit because - since even some of the speeches are set to Tim Sutton's pretty, doleful melodies - they have to lug a band around with them. No one can scamper across the stage with a double bass.

This is the sort of getting-away-from-it-all arcadia where you can't move without bumping into some celebrity showing off under a metaphorical oak tree, and in which everyone works so hard at being novel that the evening just bounces up and down on the spot. People fling themselves to the ground, fall off their bikes and scrabble on all fours across the stage. Reece Shearsmith, of the League of Gentlemen, who plays Jaques in a duffel coat, is far too full of bounce for one of the sourest characters in Shakespeare. Sean Hughes's Touchstone is pallid.

After an over-anxious start, with every phrase tricked up with a moue or a funny voice, Sienna Miller settles into being a cool Celia, giving the part an asperity of her own.She's good at showing how embarrassing and irritating it is when Rosalind (Helen McCrory) starts coming on to her would-be lover. But McCrory acts everyone off the stage, though Dominic West flourishes as a candid Orlando, despite having to wear desperate shorts when he's wrestling.

McCrory isn't as graceful as she can be, dragged into overemphasis by the hyper-acting all around her: she's too butch as a brilliantined boy; too simply passionate as a girl. Nevertheless, her passion-driven antics and her ability to go from jaunty to melting produce some enthralling moments in a hodge-podge production.

Ten years ago, a satirical Viennese cabaret, translated into English as Kamp!, staged lyrics written by the inmates of Theresienstadt, the model internment camp just north of Prague which was displayed by the Nazis to International Red Cross delegates. The Nazis' aim was to indicate that rumours of a Holocaust were without foundation. They convinced the inspectors.

Juan Mayorga's Way to Heaven, freshly translated by David Johnston, begins a version of the story from the viewpoint of an imaginary Red Cross visitor. Walking round the camp, he sees bright scenes: a cheery balloon-seller, a little girl playing with her doll, a courting couple. People speak quaintly; the guide's eulogy to the town clock sounds stiff; there's a smell of fresh paint.

But no one suggests that this strangeness could be alarming. And, surely, no observer could have guessed that each of these scenes was scripted and rehearsed like a play, with participating inmates given some hope of survival. Backtracking, Mayorga shows a Nazi commandant indulging his relish for culture by organising these rehearsals: tailoring the script, refining the accompanying gestures. An inmate, drained of hope, helps him to finesse the scenes, realising this is a way to make some inmates less dispensable.

Ramin Gray's absorbing production sends the audience on a tour of the camp: there's no fixed seating, so that spectators can scrutinise each scene from all angles, as if they were inspectors. When they go into the plain black box of the Court Upstairs, the world outside (well, Sloane Square) is at first visible; then the shutters are pulled across the windows and you're encouraged to look only at what you see in front of you. Pretty much as the Red Cross man was.

Theatre sisters usually come in threes: Lear's daughters, Chekhov's sibs, Macbeth's witches, Cinderella's two uglies and a belle. Now Helen Cooper has created a trio to join the pantheon. Or so it seems when three women convene after a long separation and talk about music, a dead father and the birth of a child.

With snail-like slowness, it becomes apparent that what's being unveiled is a mental landscape, an internal debate. That's why it sounds so artificial; that's why it crawls from one gnomic utterance to another: 'It doesn't really matter. And yet it's all that matters.'

In directing Three Women and a Piano Tuner, Samuel West has done all that he could to create tautness: strings scrape between scenes; piano wires stretch in diagonals across the stage. Phoebe Nicholls is at her best: picking away at imaginary bits of fluff on her coat; flashing vacant, bright smiles; not letting anyone see whether she's nice or nasty. It's all impeccably turned out. But it's a Duchess of Windsor play: too skinny for its jewels.